HALE-ALOHA 4A: Chief Scientist Report

Chief Scientist: T. HOULIHAN

Chief Scientist Report HALE ALOHA 4A
April 27-30, 1998
Moana Wave

The HALE ALOHA mooring cruise for the fourth deployment of our array
was augmented by one day to include time for recovery of a deep ocean
current meter array that was deployed a year earlier at the Maui sill.
This array included current meters for Pierre Flamment and Seacats for
Roger Lucas.  We also were able to schedule time for a carbonate
dissolution array with experiments designed by Paul Troy and Angela
Adams.  Three CTD's were scheduled and completed, a 1000m cast at the
buoy site for calibration of the instruments, a 4627m CTD at the Maui
sill and a 4875m CTD at the Maui deep.  Included in the CTD package was
a Sontek LADCP for logging current meter data throughout the CTD
casts.  This data was processed on board by Eric Firing and Daryl
Slocum.  A test cast was done immediately following the CDA deployment
and this cast also collected LADCP data.

We departed Snug at 0900 and all members of the science party were
required to attend a fire and abandoned ship drill at 0926 followed
immediately by a safety meeting in the ship lounge.  At 0942 the port
main engine was secured due to a coolant problem and was back on line
at 1435.  We arrived on at the carbonate dissolution array deployment
site, 22 08.3'N, 158 11.7'W, at 1825 and began deployment at 1848 over
the stern.  The array was away at 2033and at position 22 08.9'N, 158
12.5'W.  The 1000m test cast was started at 2051 and completed at 2133
when we departed for the buoy site and deployment.

We arrived on site at 2255 and the buoy was deployed at 2340.  During
the buoy deployment an anemometer, part of the meteorological package
was broken.  The anchor was dropped at 0548 and 22 23.92'N, 158
04.19'W.  We immediately began a 1000m CTD to collect water for
calibration purposes for the instruments.  Samples collected include,
nutrients, low level nutrients, DO, chl a and samples for Chuck Stump.
The cast was completed at 0732.  Buoy located at 22 22.7'N, 158
04.4'W.

We transited to the current meter mooring site, the Maui Sill, 22
37.29'N, 156 57.76'W and arrived at the first triangulation position at
1427 and completed the triangulation at 1500.  The first near bottom
CTD was started at 1525 and completed at 1830 reaching a maximum
pressure of 4626db.  The weather had deteriorated to the extent the we
decided not to attempt to recover the array at night so we changed
plans and headed to the Maui deep site for another near bottom CTD.

The Maui deep station, and 22 13.5'N, 156 36.5'W, was manned at 2210.
After some initial difficulties with the CTD configuration software the
CTD was started at 2332, completed at 025 4/29, and reached a maximum
pressure of 4875db.  We did not receive confirmation of bottle closure
during the cast and this was confirmed upon recovery as no water was
collected.  The problem was solved but there was not enough time to
attempt another cast so we returned to the Maui sill site for current
meter recovery.

The triangulation done previously was used to calculate the position of
the current meters and we returned to this site and sent the acoustic
command to release.  We arrived at the station, 22 37.15'N, 156 57.9'W,
at 0555, released the meters at 0620 and the hardhats were spotted on
the surface at 0702.  At 0719 we had hooked the array and 0739 the
array had been recovered.

We now set course for the carbonate dissolution array which had been
deployed on the first day and was being tracked by ARGOS satellite.
The array was intercepted at 1454 and the floats were hooked at 1506.
The recovery was completed at 1705.

The last event for the cruise was to return to the buoy due to the
navigation hazard light being covered.  The buoy was located at 22
23.7'N, 158 05.1'W and a zodiac was launched.  We climbed aboard the
buoy to remove the covering from the light and also to assess the
damage incurred during deployment.


Cruise Participants:

1.   T. Houlihan	UH
2.   D. Hebel		UH
3.   D. Sadler		UH
4.   L. Fujieki		UH
5.   M. Valenciano	UH
6.   D. Wright		UH
7.   C. Stump		UW
8.   S. Poulos		STAG
9.   D. Gravett		STAG
10.  P. Walz		MBARI
11.  D. Slocum		Sontek
12.  R. Lumkin		UH
13.  A. Adams		UH
14.  P. Troy		UH
15.  E. Firing		UH
16.  R. Letelier	OSU